Apparatus for tilting bulldozer blades



H. SORENSEN APPARATUS FOR TILTING BULLDOZER BLADES 4 Sheets-Shee t 1 Filed Oct. 4, 1940 HAROLD ENSEN %-IVENTOR.

April 15, 1941;

APPARATUS FOR rIm INb Filed Oct. 4, 1940 H. SORENSEN BULLDOZE R BLADES 4 Sheets-Sheet 2 Hmow SORENSEN INVENTOR;

ATTORNEY April 15, 1941. H. SORENSEN I I APPARATUS FOR TILTING BULLDOZER BLADES Filed 001;. 4, 1940 4 Sheets-Sheet 5 flTTORNEY April 15, 1941.

H. SQRENSEN APPARATUS FOR TILTING BULLDOZER BLADES Filed Oct. 4, 1940 4 Sheets-Sheet 4 HAROLD SORENSE'N INVENTOR.

BYJ- I A T is/3J5) WW J HH/ W I PatentedApr. 15,1941

' UNITED ,sTATEs' ATENT OFFICE. h f 2,238,343 v I aeraaarus FOR run-mo nULLnozEa Harold Sorensen, Knappa, Oreg. Application October 4, 1940, Serial No. 359,652

, 25 Claims.

My invention, defined broadly, relates to a scraper or bulldozer blade and its related structure; and, when defined-specifically, the inven- It is now common practice to provide some.

, tion relates to ascraper or bulldozer blade and when building roads or trails, and grading the same, to compensate for any differences in the contour, composition, and geologic formation of the ground through which a road or trail is being built and-to create a. greater crowding force on certain portions of the blade in order to compensate for these varying factors.

' Another object of-the invention blade-tilting means which receives its power from means on bulldozers. for varying the vertical P the vehicle to which the bulldozer assembly is angle as well as the are presented by a scraper or bulldozer blade to the/surface being worked;

This is necessary. because not the least of the problems of road and trail building is to ercome the difliculties presented by terrain which possesses uneven topographical features, varying geologic formations and varying 'composition and texture. Furthermore, tin many instances in building roads and trails, it is necessary to cut. and gouge the road or trail grade on the side,

of ahill and the bulldozer-carrying vehicle must necessarily assume the same angle as the hill until the grade is suiliciently. cut into the side of the hill to make a roadway large enough for the vehicle to travel thereon. It is evident, therefore, that unless some means are provided to allow the scraper or bulldozer blade to assume an angle diflerent from the angleoi repose of the hillside. the cutting and gouging of a grade through. a hillside by a tractor and bulldozer assembly would be extremely diillcult, if not impractical. It must also bepointed out that road grading requires crowning of the grade and ditching on each sidethereof. 7 a

It is within the contemplation and the very essenceof the invention to provide improvedmeans for raising or lowering one side of the irameand thereby to tilt and vary the angle ,of the scraper or bulldozer blade from its normal dozer assembly is attached is traveling and withattached.

A. very important object of the invention is to provide means for raising and lowering one side 01 the blade while the vehicle to which the bullout the necessity of the operators leaving his working position, thereby materially reducing the amount of time. and efiortpresently required to adjust the position and angle of the blade.

. Still another object of the invention and one of substantial importance is to provide means for permitting the operator of a tractor to which the bulldozer assembly is attached ior changing the position-of the blade so that the degree of bite of theblade and the amount of work to be per- Iormed'by the blade may be varied to meet the needs at hand.

Another object oi, the invention is to providemeans to permit the operator of the vehicle to which the bulldozer assembly is attached to bladewill be varied accordingly and thus cause.-

one or the other end oi the blade todo a' proportiqnately greater amount of the work' by ,cut-

ting at a proportionately greater angle to the horizontal.

One of the important objects 01' this invention is to provide manually operated means for 'per-' horizontal position -so that the pressure on the regulate the amount of work to be performed by various portions of the blade during road building operations and to obtain the greatest cutting efficiency from the blade and with a lesser amount oi eflort, time and expense.

A full and complete understanding of the invention and its objects and advantages may be obtained froma consideration of the following detaileddescription which, for clarity, must be read in connection withthe disclosures in the accompanying drawings forming apart of this specification and 'depicting'several embodiments or the invention and-in which:

bodying the principles of my invention, showin its position relative to a tractor indicated in dotted lines? Figure 2 is an end view taken on line 2-2' of Figure 1 looking in the direction indicated, partly in section and partly broken away, disclosing the structural ieatures of the power take-oft, power means for varying the angle of the blade from its normal horizontal position inorder to'permit transmitting means, and that part of the bladesupporting frame which embodies the principles the operator of a tractor and bulldozer assembly, 55.01 myinvention;

is to I provide Figure 1-is a side view of the apparatus emon line [-4 of Figure 2 looking in the direction indicated, showing the details of the power takeoff and power transmitting mechanism;

' Figure 5 is a front elevation, diagrammatically shown, of a scraper or bulldozer blade whose position relative to the tractor is controlled by the tilting means embodying my invention, illustrate ing, in dotted lines, the maximum degrees of tilt from the normal position of the blade and, in full lines, the normal position of the blade; v

Figure 6 is a side view of the apparatus embodying the principles of my invention, showing its position relative to a tractor indicated in dotted line and having slightly modified structural features;

Figure 7 is a top view, taken on line Il of Figure 6 looking in the direction indicated, of the apparatus embodying the principles of my in-- vention.

Figure 8 is an end view, partly in section and partly broken away, taken on line 8-8 of .Figure out in any way impairing the effectiveness of the invention.

Figures 1 to 4 inclusive illustrate the preferred embodiment of my invention and in Figure 1 is shown, in dotted line, a tractor of conventional design, designated generally, for purposes of this description, by reference character A. This tractor, as shown, should be considered as representative of all those types of vehicles with which my invention may be joined. A scraper or bulldozer blade |,,either of conventional design or possessing the'characteristics of the scraper or bulldozer blade shown in the above cited patent, is positioned in front-of the tractor and is sup ported by and secured to aframe of conventional design or possessing the structural characteristics of the framedisclosed in said patent. However, only the side beam 2 of the blade-supporting frame is shown, since it is the only part which is structurally altered in order to practice the An eye 3 may'have a cable (not shown) secured thereto for the purpose of placing the frame and the blade out of contact with the ground and to allow the tractor, to be used for other purposes. The side beam 2 has a vertically slotted end-portion 4 (the structural char- 6 looking invthe direction indicated, showing additional details of construction of the apparatus embodying the principles of my invention;

Figure 9 is a perspective front view of a fragmentary portion of the supporting member for the side beam and related structure embodying the invention shown in Figures 6 to 10 inclusive;

Figure 10 is a fragmentary section, taken on line Ill-l0 of Figure 6, looking in the direction indicated, disclosing additional details of construction of the apparatus embodying the prin-' ciples of my invention;

Figure 11 is a side elevation of apparatus disclosing another modified embodiment of the principles of my invention, showing the bladein normal horizontal position;

Figure 12 is a side elevation of the apparatus shown in Figure '11, showing the blade in raised position;

Figure 13 is a front elevation, diagrammatically shown, of a scraper or bulldozer blade, the

position of which is controlled by the tilting means shown in Figures 11 and 12 and illustrating, in dotted lines, the maximum degrees of tilt from the normal position of the blade;

Figure 14 is a fragmentary section, taken on line ll-ll of Figure 11 looking in the direction indicated, disclosing some structural details of the modified embodiment of my invention; and

Figure 15 is a sectional, side view of the. hearing assembly employed in the apparatus disclosed in Figures 11 to'13 inclusive, showing its structural characteristics. a

In the following detailed description of the invention the same reference characters will serve to identify corresponding and like parts in the several views of the accompanying drawings. This application is a continuation in part of my pending United States application for the improvements in Bulldozer tilting devices for' self track-laying tractors, flied April 4, 1940,

Serial Number 327,922. A scraper or bulldozer blade of the'type disclosed in my United States Patent "No. 2,230,704, for the improvements in Bulldozer construction, issued February 4, 1941, although not illustrated in the drawings which are a part of the present application, may

acteristics of which may best be seen from an examination of Figure 3), which may be secured,

thereto in any appropriate manner or made an integral part thereof. Confined within the slot 5 of the end-portion l is the stub shaft or framesupporting pin 6 which itself is rigidly secured in any manner to the track frame of the tractor A, as bestshown in Figure'2 at I. An appropriate removable guard 8 is secured to the stub shaft or pin 6 in order to securely hold the side beam on the stub shaft or pin. The .width of the slot 5 is slightly greater than the diameter of the stub shaft 6 so that the side beam 2 may have some lateral movement.

A casing 9 is secured to the track frame of the tractor A by means of an appropriately shaped bracket l0 which is held in fixed relation to the track frame by well-known anchoring means. A

splined shaft II is appropriately 10 in casing 9 and extends outwardly fr ed withone end of the casing, as best shown in Figure 4. A worm gar I2 is conventionally secured to that part of shaft II which extends outside of the casing 8. A sleeve II is slidably keyed to that part of shaft II which is confined within the casing 9. A beveled pinion I4 is secured to one end of the sleeve casing O by means of a ball and socket Joint, as

shown at IS. The control lever extends upwardly from and also intothe interior I! of the casing and has its end 20 bifurcated to form fingers 2| 4 and 22 that are secured in any desirable fashion to the sleeve II. The portion of control lever I which extends above the top ll of casing 9 is itself-joined to link 23. A bracket 24 secured to the seat of the tractor A supports the link 23.

By this arrangement the operator of the tractor has easy access to the control lever and can manipulate the position of the sleeve l3 relative to the splined shaft H without expending a great deal of effort or time.

An examination of Figures 2 and 4 will disclose another shaft 25 which is appropriately journaled to and positioned centrally of and extends be substituted for the blade shown thereinwithto a limited, degree into the interior I! of casing 9. Shaft 29 lies in the same plane as shaft ll substantially larger than the diameter of either,

of the beveled pinions l4 and II but not large enough to contact either of the beveled pinions,

when the sleeve i3 is positioned equidistant from the .sides of the casing 9. Thus it becomes evident that in orderto permit either one of the beveled pinions l4 and I! to contact and mesh with the beveled gear 21, it is necessary to slide the sleeve I3 on shaft II and that under no condition is it possible to have both of the beveled pinions coact and mesh with the beveled gear 27. A bracket 28 extends from the casing 9 and has a stub shaft 29 extending therefrom. A worm wheel 39- is rotatably disposed on stub-shaft 29 and at all times coacts' and meshes with the worm l2. A wrist pin 3| extends outwardly from the worm wheel 39 and a like wrist pin 32 extends outwardly from the upperportion of the vertically slotted portion 4 of side beam 2. A connecting rod 33 is secured to the wrist pins 3| and 32.

Sprocket 29 is directly aligned and at all'times contacts the track pins 34'', one of which is shown in dotted line in Figure 2 for purposes of description and illustration, so that when the track of the tractor A is actuated, its forward motion will impart rotation to the sprocket 29 and ln turn cause the rotation of beveled gear 21. By this means it becomes evident that any rotary motion imparted to the beveled gear 21 can readily be imparted to either one of the pinlons l4 and I and regardlessof which of the pinions is in fact dotted line at 39. A large gear wheel 3| is secured to shaft 29 and is positioned in direct ali nment and is at all times in mesh with the gear ring 35. It is evident from the foregoing that the'rotary motion of the tractor-driving sprocket 34 is transmitted to the large gear wheel .31

rotated, rotation will be imparted to the worm l2 and tothe worm gear 39. By means of the connecting rod 3i, the rotary motion of the foregoing train of gears is translated to reciprocatory motion so that the side beam 2 may be raised or lowered-to aqdistance determined by the throw of the crank worm wheel '39.

In Figure 5 the uppermost and lowermost position which the blade I may assume from its paratus heretofore described, the position of the other side of the frame and blade is changed'to a slight degree. This is possible because the'stub through the intervention of gear ring 39 so that the beveled gear "is rotated and the vrotary motion is transmitted to the worm l2 in a manner heretofore pointed out in describing the invention disclosed in Figures 1 to 4 inclusive of the drawings. A supporting bracket 39 is secured to the track frame of tractor A in any desirable manner. Supporting bracket 39 has three bear- -ings,39, 49 and 4| extending outwardly, there'- from indirect alignment with each other. A shaft 42 is rotatably disposed within bearings 39,

-49 and 4| and collars 49' and 4i surrounding shaft 42prevent'any axial movement thereof.

The lower part'of the shaft 42 has a worm thread formed therein, asshown at 43, and a worm wheel 44 is secured to the top portion-of the shaft 42, so that it may at all times mesh and be driven by the worm l2.

Also formed in the supporting bracket 39 is a vertically-disposed groove 49 and a vertically-disposed slot 49 spaced apart from each other but in registerable alignment, as shown in Figure 9,

so that side beam 2 can easily enter the. space between themras shown in Figure 10. An internally threadedsplit collar 41 is appropriatelyv secured between the sides of and near the end '49 of side beam 2 and is positioned so that it is in registerable alignment and in threadable engagement with the threaded-portion 43 of shaft '42. A pair of oppositely disposed stub shafts or rotation of the worm wheel 44,. the side beam 2 may be raised and lowered through the rotation I of-v the shaft 42 and the threadable connection shaft (not shown), on which the companion side amount of angle assumed by the end of the blade nearest side beam 2.

In Figures 6 to 10 inclusive, there is shown apparatus for tilting the scraper or bulldozer blade possessing slightlydifferent structural charac teristics but embodying the principles of my invention. The power for raising and lowering the beam 2 is not obtained from the track of the tractor A but is derived from one of the tractordriving sprockets of the tractor A by attaching to the side of the driving sprocket, indicated for purposes of illustration by reference character 34, a gear ring 39 which is fixedly secured to the tractor-driving sprocket in any desirable manner and which surrounds the sprocket'hub shown in to 15 inclusive.

"rusual frame consisting of a pair of side beams SI of the collar 4'lvtherewith, permitting the pins 49 and 59 to move up or down, as the case may be, in their respective groove and slot. The

blade I and its supporting framewill respond to the foregoing described apparatus to produce the conditions.diagrammatically 'shownin Figure 5 and heretofore pointed out in the first pararaph of page 11 of this specification. By this arrangement of the elements, the rearward thrust, necessarily given to the side beam 2 when blade I is forced to out into the terrain being worked, is taken on the'pins 49 and 59 and on the supporting bracket 99 and not on the shaft 42 and collar 4'l.

There is shown in Figures 11 to 15 inclusive apparatus for tilting the blade and its supportingframe which possesses somewhat modified structural characteristics but which performs substantially the same functions that are-'performed bythe apparatus for tilting the bulldozer blade heretofore described. The control and power transmission-mechanism is identical with that heretoforedescribed in connection with the apparatus shown in Figures 6 to 10 inclusive and therefore will not be described in connection with the description of the structural characteristics of the rest of the apparatus shown in Figures 11 This apparatus includes the and 5| disposed one on each side of the tractor.- The rear end of each side beam is pivotally supported on the track frames of the tractor by the pins 6; only the one supporting side beam 5| being shown, and the front end of each side beam is pivotally connected to the blade 52 as shown at 53. A hearing block 55 is welded or otherwise secured to the side beam 5| near the pivotal connection of the side beam to one of the track frames of the tractor. A cylindrical member 55 is movably confined in bearing block 55 and is held therein by thrust collars 5B and 51. The interior of the cylindrical member 55 has an internal thread formed therein as shown at 58. A spline 59 is joined by universal joints 60 and 8| to the cylindrical member 55 and shaft respectively so that when shaft II is rotated the cylindrical member 55 also is rotated.

A sliding member 62 is slidably disposed and guided on side beam 5| and a rod 63 is secured tothe'top of the sliding member 62. Rod 63 is externally threaded at its other end as shown at 64 and this threaded portion is at all times in engagement with the internal thread 58 formed in the interior of the cylindrical member 55. It at once becomes clear that upon the rotation of the-internally threaded cylindrical member 55 the rod 63 will be drawn into or out of the interior of the cylindrical member 55, depending on the direction of rotation of member 55, and thereby force the sliding member 62 to travel towards or away from the bearing block 54.

A thrust brace 55 is pivotally secured to the blade 52 as shown at 6B and to the top of the sliding member 62 as shown at 61. The other end of the blade 52 is braced against appreciable movement by means of a brace, not shown, disposed between the blade and the side beam 5|. When it is desired to tilt the blade so that it will assume the position shown in Figure 12 and the dotted line position as shown at 68 in Figure 13, the sliding member 52 is forced to move forwardly on beam 5| from its normal position as shown in.,Figure 11 by means of the rotation of the cylindrical member 55 forcing the rod 53 out of 'its interior 58. This forward thrust must necessarily be taken'by the brace 65 and the thrust between the thrust brace and the forward portion of the side beam 5| causes the blade 52 and the whole side beam 5| to be raised, as

shown, while the other side of the blade and its rod 33, the side beam 2 is either raised or low- ,ered. Since it is desired to permit the operator his seat, the gear shifting mechanism employed as heretofore allows the blade to be tilted either to the right or to the left by translating and transmitting the power derived from the track of the tractor, stated, to raise or lower the side beam 2.

The operation of the first modified embodiment, heretofore described and disclosed in Figures'fi to 10 inclusive, is substantially the same, except that the blade I and the beam 2 is raised or lowered by rotating shaft 42 to which the collar 41 is threadably engaged. Finally, the tilting of the blade 52 by the second modified embodiment to assume the position shown in dotted lines in Figure 13 is accomplished by the use of a sliding member slidably disposed on the side beam 5| that has a rod connected to it which, in

turn, has its free end forced inwardly or outwardly from the threaded interior of the cylindrical member 55 that is rotated and derives its power from the shaft operated by the train of gears and which, in turn, derives its power from the driving sprocket of the tractor A.

In all of theembodiments heretofore described and shown in the drawings, the raising .or lowering of .the blade can be and is intended to be nite structural characteristics and forms. To

these details of disclosure, the invention, of course, is not limited, since what is claimed as new and whatis desired to be secured by Letside beam remain in substantially the same posi-" tion except that there is created a slight twist thereon to the right. When it is desired that the blade 5| assume the position shown in dotted lines at 59 in Figure 13, the sliding member 52 is caused to move rearwardly on side'beam 5| byrotating cylindrical member and causing it thereby to pull the rod 83 into the interior. 58. Of course, it is obvious that the desired degree of tilt on blade 52' is determined by the amount of forward or rearward movement of the sliding member 52'from its normal position on the side beam 5| as shown in Figure 11.

Operation From a reading of the foregoing description and an examination of the preferred embodiment 'of the invention disclosed in Figures 1 to 4 inclusive, it will be seen that, in order to tilt blade I to the maximum degrees of tilt shown in Figure 5 015, to 'any degree less than the maximum,-

rotation is imparted to the main beveled gear ters Patent is set forth in the appended claims.

I claim:

1. In apparatus of the class described, comprising, in combination with the running gear of a conventional type of tractor and the bulldozerblade supporting frame, of means operatively associated with the running. gear of the tractor and one side of the frame for raising or lowering that side of the frame to thereby raise or lower the bulldozer blade into different angular positions relative to the front of the tractor and means associated-with the first-mentioned means for selectively-connecting said means into operative relationship with the running gear of the tractor.

2. In apparatus of the class described, comprising, in combination with one of the tracks of a. conventional type of tractor and the bulldozer-blade supporting frame, of means oper- "atively associated with one of the tracks of the. tractor and one side of the frame for raising or lowering that side of the frame to thereby raise or lower the bulldozer bladeinto different angular positions relative to the front of the tractor. and means associated with the first-mentioned means for selectively connecting said means into operative relationship with said track of the tractor. t

3. In apparatus of the class described com- A -prising, in combination with one of the driving runninggear and the bulldozer-blade mounting the bulldozer-blade supporting frame, of means operatively associated with said driving sprocket Q of the tractor and with one side ,ofthe frame for raising or lowering that side, of the frame to thereby raise or lower the bulldozer blade into different angular positions relative to the front of the tractor, and means associated with the first-mentionedmeans forselectively connecting said means into operative relationship with said driving sprocket of the tractor.

4. In apparatus of the class described, comprising, in combination with the running gear of a conventional type of tractor and the bull,- dozer-blad'e supporting frame, of a tram of gears, means operatively connected to the running gear of the tractor for transmitting power from the tractor to the train of gears, means associated frame, of means operatively associated with-the .running gear pf-the tractor andone side of the frame forraising or lowering that side of the frame to-thereby raise or lower the bulldozer g with the train of gears and one side of the frame for raising or lowering that side 'of the frame to thereby raise and lower the bulldozer blade into different angular positions relative to the front of the tractor, and'means associated with'the train of gears for selectively connecting some of said gears into operative relationship with the power transmitting means.

5. In apparatus of the class described, comprising; in combination with one of the tracks of a conventional type of tractor-and the bulldozerblade supporting frame, of a train of gears, means blade into different angular positions relative to the front of the tractor, said means having driving and driven shafts and cooperativegears se-' cured thereon, and clutch means associated with the driven shaft of the first-mentioned means for selectively connecting thefdriving shaft into operative relationship with the driven shaft for determiningthe direction of rotation of thedriven shaft and the gears secured thereon.

9. Apparatus for moving a bulldozer blade into J desirable working positions, comprising, in com- I bination with'a' conventional type of tractor, its running gear and the bulldozer-blade mounting frame, of means operatively associatedwith therunning gear of the tractor and one side of the frame for raising or lowering that side of the frame to thereby raise or lower the bulldozer blade into difierentangular positions relative-to the front of the tractor, said means 'havingdriving and driven shafts and cooperative gears secured thereon, means for rotating the driving operatively connected to one of the tracks of the tractor for transmitting power from the tractor to the train of gears, means associated with thetrain of gears and one side of the frame for raising or lowering that side of the frame to thereby raise and lower the bulldozer blade into difierent angular positions relative to the-front of the tractor, and means associated with the. train of gears for selectively connecting some of saidgears into operative relationship with the. power transmitting means.

6. In prising, in combination'with one of the driving sprockets of a conventional type of tractor and the bulldozer-blade supporting frame, of a train 'of gearsfmeans operatively. connected to one of the driving sprockets of the tractor for transmit- 'ting power from thetractor to the train of gears, 1

means associated withthe train of gears, and

one side of the frame for raising or lowering that side of the frame'to thereby raise and lower the bulldozer blade into different angular positions relative to the front of the tractor, and means associated with the train of gears for selectively connecting some of said gears into operative relationship with the power transmitting means.

'7. In apparatus of the class described, comprising,

of tractor and a bulldozer-blade supporting apparatus of the class described, com-' in combinationwith a conventional type driven shaft of the first-mentioned means for selectivelyco'nnecting the driving shaft into operative relationship with the driven shaft for, del termining the direction'of rotation of the driven shaft and the gearssecured thereon.

- 10.,A'pparatus for moving a bulldozer blade into desirable working positions, comprising, in combination with aconventional type of tractor, its running gear and the bulldozer-blade mounting frame, of means operatively associated with. 'the running gear of the tractor and one side of v the frame for raising or lowering that side of the frame to thereby raise or lower the bulldozer blade into different angular positions, relative to the front of the tractor; said means having driving and driven shafts and cooperative gears secured thereon, means for rotating the driving the gears-secured thereon, and manually actuated means for engaging or disengaging the clutch means. 11. Apparatus for moving a bulldozer blade into desirable working positions, comprising,.in

cured at their rearward ends to each side of the .track frame of the tractor, a ground-working frame, of a train of gears, means operatively convnected to the running gear of the tractor for transmitting power from the tractor to the train of gears, means associated with the train of. gears and one side of the frame for raising or lowering that side of the frame to thereby raise or lower the bulldozer blade into different angularpositions relative to the front of the tractor, and.

manually operative means associated with the.

train-of gears for selectively connecting some of said gears into operative relationship with the power transmitting means. v

8. Apparatus for moving a bulldozer blade into desirable working positions,1comprising, in combination with a conventionaltype of tractor, its

blade mounted to its supporting frame forwardly of the tractor, and meanssecured to one'side of the tractor and operatively associated with it's -ru ning gear and with one of the side beams of the-blade-supportingframe for moving the blade and that side pf the frame intojdifferent operof beveled 'pinions secured.

ning gear and with one of the side beams of the blade-supporting frame for moving the blade and that side of the frame into different operative positions relative to the front of the tractor, and means associated with the first-mentioned means for selectively connecting said means into operative relationship to the running gear of the tractor.

13. Apparatus for moving a bulldozer blade into desirable working positions, comprising, in combination with a conventional type of tractor and its running gear, of a bulldozer-blade mounting frame, comprising a pair of side beams secured at their rearward ends to each side of the track frame of the tractor, a verticallyslotted member secured at the end of one of said side beams, a ground-working blade mounted to its supporting frame forwardly of the "tractor, means secured to one side of the tractor and 'operatively associated with its running gear and with the vertically-slotted member of one of the beams of the blade-supporting frame for moving the blade and that side of the frame into different operative positions relative to the front of the tractor, and manually operative means associated with the first-mentioned means for selectively, connecting said means into operative relationship with the running gear of the tractor. i4. Apparatus for raising or lowering one end of the blade mounting frame, a rod secured to the worm gear and to the vertically-slotted member, whereby upon the rotation of the worm gear, the side beam will be raised or lowered, means slidablypositioned upon the driven shaft adapted to permit the selective transmission of rotary motionfrom the sprocket to the worm gear, and manually operated means for shifting the lastmentloned means.

17. Apparatus for raising and lowering one end of a bulldozer blade to vary the working angle of the blade relativeto the ground} comprising a casing, a driving shaft extending into and from the casing, a gear wheel secured to one end of said shaft, a beveled pinion secured tothe'other end of said shaft, a driven shaft journaled in saidcasing' and having one end extending outwardly therefrom, said driven shaft lying in the of a bulldozer blade to vary the working angle of 3 the bla'derelative to the ground, comprising a casing, a driving shaft extending into and from the casing, a driving sprocket secured to one end of said shaft, abeveled pinion. secured to the,

other end of said shaft, a driven shaft journaled of the driven shaft,"a worm gear at all times in 40 mesh with said Worm, a vertically slotted member secured to the end of one of the side beams of the blade mounting frame, a rod secured to the worm gear and to the vertically-slottedmember, whereby upon the rotation of the worm gear,

the side beam will be raised or lowered, and means slidably positioned upon the driven shaft adapted to permit the selective transmission of rotary motionfrom the sprocket to the worm ear. g 15. Apparatus characterized as in claim '14 wherein the means that is slidably positioned upon the driven shaft adapted to permit the selective transmission of rotary motion from the sprocketto the worm gear comprises a'sleeve slidably positioned on the driven shaft, and a pair to the end of said sleeve, 'said pinions having the same structural characteristics and adapted to mesh, one" at a 1 time, with the beveled pinion secured to the driving shaft. V

16.. Apparatus for raising and lowering one end of a bulldozer blade to .vary the working angle of the blade relative to' the ground,comprising a casing, a driving shaft extending into and from thelcasing, a driving sprocket secured to one end of said shaft,- a beveled pinion secured to the other end of said shaft, a driven shaft journaled in said casing and having one end extending outwardly therefrom, said driven shaft lying in the same plane but positioned at right angles to the driving shaft, a worm keyed to the extended end of the driven shaft, a'worm gear at alltimes in mesh with said-worm, a vertically-slotted mem-.

same plane but positioned at right angles to the 7 driving :shaft, a worm keyed to theextended end of the driven shaft, a'worm'gear, at all times in mesh with said worm, a vertically positioned shaft for holding said worm gear, said shaft having an external thread around its lower portion, an internally threaded collar secured to the end of the side beam and threadably engageable by the externally threaded shaft, a pair of directly aligned pins'extending from opposite sides of the collar, a bracket for supporting said externally threaded shaft and said pins, said bracket having'a groove and a slot registerably aligned into which the pins fit, whereby, upon the rotation of the threaded shaft by the worm gear, the side beam will be raised or lowered, and means slidably positioned upon the driven shaft adapted to permit the selective transmission of rotary motion from the gear wheel to the worm gear.

18. Apparatus characterized as in claim 17 1 wherein the means that is slidably positioned upon the driven shaft adapted topermit the selective transmission of rotary motion from the sprocket to the worm gear comprises a sleeve slidably positioned on the driven shaft, and a pair of beveled pinions secured to the ends of said sleeve, said pinions having the same structural characteristics and adapted to mesh, one at a time, with the beveledpinion secured to the'driving shaft. 3 19. Apparatus for raising and lowering one end of a bulldozer blade to vary the working angle of the blade relative to the ground, comprising a casing, a driving shaft extending into and from the casing, a gear wheel secured to one end of said shaft, a beveled pinion secured to the other end of said shaft, a driven shaft joumaled' in said vcasingand having one end extending outwardly therefrom, said driven shaft lying in the same plane but positioned at right angles to the driving shaft, a worm keyedto the extended enlist the driven shaft, a worm 1 gear at all times in mesh with said worm, a

vertically positioned shaft for holding said worm gear, said shaft having an external thread around its lower portion; an-intemally threaded threadably threaded shaft, a bracket for supporting said collar secured to the end of the side beam and engageable by the externally externally threaded shaft and said collar, means ber secured to the end of one of the side beams the selective transmission'of rotary motion from 6 formed in said bracket and mociated with said or similar vehicle, an approximately U-shaped frame movably connected to @idtractor orsimilar vehicle, said frame comprising a pair of side beams disposed on each side of the vehicle and extending forwardly thereof, a vertically-slotted member secured to the end of one of the side beams, a scraper or bulldozer blade connected to the front of said frame, a gear casing secured to the side of the tractor or similar vehicle, a

plurality of selectively coacting gears disposed in said casing, manually actuated means associated with said gears for permitting the operator of the tractor to selectively determine the actuation of said gears, means for taking power from the tractor for operating said gears, and means secured to the vertically-slotted member for translating and transmitting the rotary motion of the gears to reciprocatory motion and thereby either raise or lower one side of said frame and vary the angular position of the blade relative to the ground.

21. In apparatus of the class described, in

or similar vehicle, an approximately U-shaped frame movably connected to said tractor or similar vehicle, said frame comprising a pair of side beams disposed on each side of the vehicle and extending forwardly thereof, a bracket secured to the side of the tractor, said bracket having formed therein an elongated groove and an'elongated slot vertically disposed and registerably aligned with each other. meansv secured to one of said beams and slidably associated with said bracket for supporting and permitting the raising and lowering of said beam, a'scraper or bulldozer blade connected to the front of. said frame, a gear casing secured to the side of the tractor or similar vehicle to which the bracket is. secured, a plurality of selectively co-acting gears disposed in said casing, manuallyactuated means associated with said gears for permitting the operator of the tractor to selectively, determine the actuation of said gears, means for taking power from the tractor for operating said gears, andmeans threadably secured to the side beam supporting means and operatively connected to the gears for raising or lowering said side beam and thereby vary the angular position of the blade relative to the ground.

22. Apparatus for raising and lowering one end of a bulldozer blade to vary the working angle of the blade relative to the ground, comprising a casing, a driving shaft extending into and from the casing, a gear wheel secured to one end of said shaft,.a beveled to the other end of said shaft, a driven shaft journaled in said casing, and having one end extending outwardly therefrom, said driven shaft lying in the same plane but positioned at right angles to the driving shaft, a side beam, a bearing block secured to the side beam, an internally threaded cylindrical member rotatably confined within the bearing block, a spline universally secured to one end of the internally threaded cylindrical member and to the driven shaft, 9. rod threadably secured to the interpinion secured combination with a conventional type of tractor nally threaded cylindrical member, means secured to the rod s'lidably'positioned on the beam and indirectly connected to the blade, whereby, upon the rotation of the threaded cylindrical member, the side beam and the blade will be' raised or lowered, and means slidably positioned upon the driven shaft adapted to permit the selective transmission of rotary motion from the gear wheel to the internally threaded cylindrical member.

23. Apparatus characterized as in claim 22, in-

eluding manually operated means for shifting the last-mentioned means.

24. Apparatus for raising and lowering one end of a bulldozer blade to vary the working angle of the blade relative to the ground, comprising a casing, a driving shaft extending into and from the casing,'a gear wheel secured to one endv of said shaft, a beveled pinion secured to the other end of said shaft, a driven shaft journaled in said casing and having one end extending outwardly therefrom,- said driven shaft lying in the same plane but positioned at right angles. to the driving shaft, a side beam, a bearing block secured to the side beam, an internally threaded cylindrical member rotatably confined .within the bearing block, a spline universally secured to one end of the internally threaded cylindrical member and to the 'driven shaft,.a rod threadably secured to the internally threaded cylindrical member, a member slidably positioned upon said side beam and directly secured to said rod, a thrust-receiving brace directly secured to said sliding member and to the blade, whereby, upon the rotation of the threaded cylindrical member, the side beam and the blade will I be raised or lowered, and means slidably positioned upon the driven shaft adapted to permit the selective transmission of rotary motion from the gear wheel to the internally threaded cylin-' drical member. 25. In apparatus of the class described, in combination with a conventional typeof tractor or a similar vehicle, an approximately U-shaped frame movably connected tosaid tractor or'similar' vehicle, said frame comprising a pair of side beams disposed on each side of the vehicle and extending forwardly thereof, a scraper or bulldozerrblade connected to thefront of said frame, a gear casing secured to one side of the tractor or similar vehicle, a plurality of selectively coacting gears disposed in said casing,

' manually actuated means associated with said gears for permitting the operator of the tractor to selectively determine the actuation of said gears, means for taking power from the tractor for operating said gears, an internally threaded cylindrical member secured to the side beam disposed on the same side of .the tractor which carries the gear casing, means associated with said internally threaded cylindrical member and operatively connected to the gears for rotating said member. and means slidably disposed on said beam. and connected to the bladeand to said internally threaded cylindrical member, whereby, upon the forward or rearward movement of said slidable m'ember caused by the rotation of said cylindrical member, the blade and the side beam will be raised or lowered accordingly.

mnonn SORENSEN. 

